Normally, an infusion set for intermittent or continuous administration of a therapeutic substance, such as insulin, is in the form of a two-part device.
A traditional infusion set comprises a base part having a cannula for insertion into a patient where the base part has means for receiving a connector cannula extending from a connector and for bringing the connector cannula into fluid communication with the cannula of the base part. Often, the connector needle is in fluid communication with a drug delivery device, such as an insulin pump.
Different kinds of infusion sets are described in WO 02/068014 A2, EP 0 956 879 A1, U.S. Pat. No. 5,522,803, U.S. 2003/0225373 A1 and WO 03/026728 A1.
U.S. 2003/0176852A1 discloses an infusion set in which a base part comprises a pivoting member, the base part comprising a cannula for insertion into a patient and pivoting member has an inner cavity with one receiving end adapted to receive an inserter needle or a piercing member and two connecting ends (316I and 320) for further connection with the cannula of the base part. During insertion, the pivoting member is positioned orthogonally to the base part and an inserter needle penetrates a membrane in the receiving end. The needle passes through a canal and through the first connecting end into the cannula which then can be inserted. After insertion, the needle is removed and the pivoting member is connected with a connector. The connector and the pivoting member are connected from the same direction as the connection between the pivoting member and the inserter. The pivoting member is then turned in order for the second connecting end to align with the cannula. This device has the drawback that it is very sensitive to movement of the pivoting member since a small turning will close off the delivery of drugs.
WO 02/094352 A2 discloses an infusion set having a base part that can receive an insertion needle from one direction and a connector needle from a second direction. This design does not allow the patient to choose the direction he/she wants to connect the connector with the base part.
In the infusion sets described above, the construction of the cannula and the means for providing fluid communication between the cannula and the cannula from the connector are unique for each set. Normally each infusion set also utilizes a specific set of guiding and/or locking members and thus allows only for a specific connector to engage with the base part.
It would be highly desirable from both a production point of view and practical use if a universal part having a cannula and means adapted to receive the cannula from the connector and fitting to most/all common infusion sets available. Aspects of the present invention are intended to cover both infusion sets as described above and variants thereof when such a universal part is used therein.
Furthermore, in the infusion sets described above, both the connector and the base part have to be substituted if the patient wishes to change to a different base part. It would be advantageous if different types of connectors could be used with the same base part and different types of base parts could be used with the same connector. It would also be advantageous if connection from different angles would be possible.